Dwyer Series 673 Pressure Transmitter, 0.25 %, 4-20 mA

Series 673 economical fixed-range pressure transmitter

The Dwyer Series 673 is a low-cost pressure transmitter with a stainless steel sensor and a 4-20 mA output at ±0.25 % accuracy. It is made as a fixed-range device, without adjustable zero and span, and is designed for harsh locations with high shock and vibration. The range extends from 0 to 1 psi up to 0 to 1000 psi, and there is a compound range of -14.7 to 100 psi.

Seven Star LLC supplies the Series 673 in Oman and the GCC as an independent supplier in Muscat. The page describes the models, the cable and conduit versions and the selection points.

Series 673 model chart

Models are numbered by range: 673-1 for 0 to 1 psi, 673-2 for 0 to 2, 673-3 for 0 to 5, 673-4 for 0 to 10, 673-5 for 0 to 25, 673-6 for 0 to 50, 673-7 for 0 to 100, 673-8 for 0 to 200, 673-9 for 0 to 500, 673-10 for 0 to 1000 and 673-14 for -14.7 to 100 psi. A C after the number, for example 673-7C, indicates the conduit version, which has a conduit connection that is tightened by hand to seal the electrical entry. The NISTCAL-PT1 option provides a NIST traceable calibration certificate.

Technical specifications of the Series 673

How the Series 673 is used

The 673 is a simple transmitter: it takes 9 to 30 V DC, senses pressure with a stainless steel element and returns 4 to 20 mA. Because span and zero are fixed at the factory, the correct range must be ordered, and the stated overpressure limit of twice the maximum range provides a modest margin for transients.

It is built for repeated duty in OEM machines, where thousands of identical units can be installed with no field calibration. The fast response of 5 ms captures pressure changes in hydraulic and compressor circuits.

The conduit version provides a standard conduit connection for installations that require wiring in conduit; the cable version has 2 ft of multiconductor cable already attached.

Series 673 versus Series 682

The Series 682 offers better accuracy (0.13 %), external zero and span trim, a welded housing and wider ranges up to 10,000 psi. The Series 673 is the choice where cost matters and fixed ranges are acceptable, such as OEM skid packages.

For hazardous areas, the Series 3200G offers an explosion-proof approval, but at a much higher price.

Selection and ordering checklist for the Series 673

• Fixed range and the maximum expected pressure
• Cable or conduit version
• Process media compatibility with 17-4 PH stainless steel
• Temperature limits
• Supply voltage
• Calibration certificate

Installing the Series 673

Screw the unit in using the hex flats, and connect the cable to a 9 to 30 V DC supply and a 4-20 mA input. For the conduit version, hand-tighten the conduit connection to ensure the seal specified.

Since adjustments are not possible, commission by checking the output against a reference gauge at atmospheric pressure and at a known pressure.

Typical applications in Oman and the GCC

Industrial OEM equipment, hydraulic systems, HVAC equipment, industrial engines and compressor control are the applications named in the datasheet. For packaged equipment shipped to Oman, the compact 65 g weight and rugged design make it a practical choice.

When specifying a fixed-range unit, remember that the full-scale accuracy of 0.25 % best-fit straight line is an absolute error band: on the 0 to 100 psi model it corresponds to about 0.25 psi. The stability figure of 0.5 % of full scale per year adds to this, so for a loop that must stay within a tight tolerance, build a regular comparison with a reference gauge into the maintenance plan and replace rather than repair a unit that drifts out of tolerance. Because the output is a plain 4-20 mA signal, a loop calibrator or a multimeter in series is enough to check the electrical side, which keeps field testing simple for maintenance teams without HART tools.

Series 673 range summary

From the model chart.

Information to send with an RFQ for the Series 673

Please send the following.

• Range and units
• Cable or conduit version
• Quantity
• Delivery date

Site conditions in Oman for the Series 673

Field instruments in Oman are exposed to strong sun, high ambient temperature, wind-blown dust and, on coastal plants, salt in the air. When you specify the Series 673, check the ambient and process temperature limits, the enclosure rating and the wetted and housing materials against the actual installation point, and consider sunshades for transmitters mounted in direct sunlight. Cable entries should be sealed with suitable glands so that dust and moisture cannot enter the housing.

Calibration and verification planning matters as much as selection. Record the range, configuration and tag data of each Series 673 at commissioning, define a check interval that suits the criticality of the loop, and keep the certificates with the plant documentation so that audits and shutdown work can proceed without delay.

Documents and quotation

The manufacturer datasheet for the Series 673 is attached on this page, so the electrical data, terminal assignment and ambient limits quoted above can be checked against the original document before an order is placed.

Seven Star LLC supplies Dwyer products in Oman and the GCC as an independent supplier in Muscat. Send the quantity, the signal types and the project delivery date, and we will confirm availability and lead time in a written quotation.